Prevalence Of Difficult Intubation Research Articles

A prediction model for difficult intubation using skeletal features in patients affected by apnea-hypopnea syndrome.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) has been linked to increased risk of perioperative morbidity and mortality because of difficult intubation (DI). However, there is a lack of clinically validated tools to identify OSAHS patients who are likely to have an increased the risk of DI. For model development, a prospective cohort study included patients with OSAHS who underwent elective surgery between September 2018 to December 2020. The outcome was DI and classified according to the Cormack-Lehane grading. Conventional airway assessment tests, skeletal features, and the severity of OSAHS were recorded, and LASSO regression was used. Validation was performed on an external sample of patients from the same hospital between January 2021 and December 2021. The development (prevalence of DI: 44%) and validation cohorts (prevalence of DI: 32%) included 247 and 82 patients, respectively. Based on the result of LASSO, age and four skeletal features (thyromental height, maximum mandibular protrusion, mandibulohyoid distance, and neck hypokinesis grade) were included in the final model. Discrimination and calibration of the model were satisfactory with high AUC (0.97), sensitivity (88.5%), specificity (94.6%), accuracy (92.7%), PPV (88.5%) and NPV (94.6%) from external validation. Our study developed and externally validated a DI prediction model using skeletal features in OSAHS patients. The final model had an NPV of nearly 95%, suggesting that a simple nomogram including only five predictors was quite helpful for ruling out the presence of difficult intubation in OSAHS patients who underwent elective surgery.

The Prevalence of Difficult Airway in Children With Beckwith-Wiedemann Syndrome: A Retrospective Cohort Study.

Beckwith-Wiedemann syndrome (BWS) is the most common congenital overgrowth disorder with an incidence of approximately 1 in 10,000 live births. The condition is characterized by lateralized overgrowth, abdominal wall defects, macroglossia, and predisposition to malignancy. Historically, children with BWS have been presumed to have difficult airways; however, most of the evidence to support this has been anecdotal and derived from case reports. Our study aimed to determine the prevalence of difficult airway in patients with BWS. We hypothesized that most patients with BWS would not have difficult airways. We retrospectively reviewed the electronic medical records of patients enrolled in our institution's BWS registry. Patients with a molecular diagnosis of BWS who were anesthetized between January 2012 and July 2019 were included for analysis. The primary outcome was the presence of difficult airway, defined as difficult facemask ventilation, difficult intubation, or both. We defined difficult intubation as the need for 3 or more tracheal intubation attempts and the need for advanced airway techniques (nondirect laryngoscopy) to perform tracheal intubation or a Cormack and Lehane grade ≥3 during direct laryngoscopy. Secondary objectives were to define predictors of difficult intubation and difficult facemask ventilation, and the prevalence of adverse airway events. Generalized linear mixed-effect models were used to account for multiple anesthesia events per patient. Of 201 BWS patients enrolled in the registry, 60% (n = 122) had one or more documented anesthetics, for a total of 310 anesthetics. A preexisting airway was present in 22 anesthetics. The prevalence of difficult airway was 5.3% (95% confidence interval [CI], 3.0-9.3; 18 of 288) of the cases. The prevalence of difficult intubation was 5.2% (95% CI, 2.9-9.4; 12 of 226). The prevalence of difficult facemask ventilation was 2.9% (95% CI, 1.4-6.2; 12 of 277), and facemask ventilation was not attempted in 42 anesthetics. Age <1 year, macroglossia, lower weight, endocrine comorbidities, plastics/craniofacial surgery, tongue reduction surgery, and obstructive sleep apnea were associated with difficult airways in cases without a preexisting airway. About 83.8% (95% CI, 77.6-88.5) of the cases were intubated with a single attempt. Hypoxemia was the most common adverse event. The prevalence of difficult tracheal intubation and difficult facemask ventilation in children with BWS was 5.2% and 2.9%, respectively. We identified factors associated with difficult airway, which included age <1 year, macroglossia, endocrine abnormalities, plastics/craniofacial surgery, tongue reduction surgery, and obstructive sleep apnea. Clinicians should anticipate difficult airways in patients with these factors.

Factors Predicting Difficult Endotracheal Intubation.

Factors Predicting Difficult Endotracheal Intubation.

Population analysis of predictors of difficult intubation with direct laryngoscopy in pediatric patients with and without thyroid disease.

There are no data on the prevalence and predictors of difficult intubation (DI) in pediatric patients with thyroid disease. This study (1) assesses the prevalence of DI in patients with thyroid disease undergoing elective operations, (2) identifies other predictors of DI in children, and (3) evaluates the effect of DI on postoperative care and length-of-stay. A single-center retrospective cohort analysis of procedures in patients assigned with an ICD-9 code for thyroid disease between June 2012 and February 2016. A comparative group was created which comprised of patients without thyroid disease receiving orthopedic or urologic surgeries to determine differences in DI prevalence. Univariate analyses compared demographics and intubation details between groups, and logistic regression identified independent variables associated with DI. Patients with and without DI were compared based on procedure duration, PACU-LOS, and escalation-of-care. DI prevalence was greater in the thyroid group (4.9%, 51/1046) compared to the non-thyroid group (2.6%, 33/1289) (OR 1.95, 95% CI 1.25-3.05; p=0.003). DI was associated with younger age, higher American Society of Anesthesiologists (ASA) class, and smaller body habitus (p<0.001 for all comparisons). Congenital hypothyroidism (OR 2.49, 95% CI 1.44-4.32; p=0.002)) and acquired hypothyroidism (OR 2.20, 95% CI 1.42-3.41; p<0.001) were seen in a greater proportion of DI patients. After adjustment for demographic confounders, age and ASA class were independently associated with DI (p<0.05), while hypothyroidism did not reach statistical significance (p=0.077). Direct laryngoscopy (DL) was most frequently used as the successful subsequent maneuver in securing the airway in DI patients. A longer PACU length-of-stay was seen after procedures with DI (p<0.001). Elective pediatric surgical patients with thyroid-related diagnoses at our institution had a higher prevalence of DI than those without thyroid disease, but this finding could not be isolated to thyroid pathology. Repeat DL achieves successful intubation in the majority of DI patients. DI patients often require longer recovery times due to prolonged cardiopulmonary monitoring.

Predictors of Difficult Tracheal Intubation on Adult Elective Patients in a Teaching Hospital

Background: During routine preoperative assessment of patients one of the commonest practices is predicting difficulty of tracheal intubation from various factors detected. Whether the factors reliably predict the difficulty is subject of argument. This study was conducted to assess the predictors of difficult tracheal intubation in adult patients. Methods: In this prospective observational study, we studied 120 consecutive elective adult patients admitted for general, gynecologic and orthopedic surgeries. Socio-demographic parameters and test variables such as BMI, TMD, SMD, IIG and Mallampati class were collected during preoperative evaluation. CL grade and difficulty of intubation were observed while the anesthetist in duty performs the laryngoscopy. While the former obtained from the preoperative anesthesia note, the latter were filled to questionnaire based on what the anesthetist reports during or after laryngoscopy. The prevalence of difficult intubation and the sensitivity, specificity, PPV and NPV of the tests were analyzed. SPSS-20 and different formulas were used during analysis. Chi square test was used and P&lt;0.05 was considered as statistically significant. Result: The overall prevalence of difficult tracheal intubation was 2.5%. The sensitivity, specificity, PPV &amp; NPV of the tests were 0%, 98.3%, 0% &amp; 97.46% for BMI; 0%, 97.5%, 0% &amp; 100% for SMD; 100%, 96.64%, 20% &amp; 100% for TMD; 0%, 99.17%, 0%, &amp; 100% for IIG; and 100%, 99.14%, 75% &amp; 100% for Mallampati test. Conclusion: The incidence is not quite small that anesthetists should use necessary tests to predict the difficult intubation. Probably combining the tests being the best option, Mallampati test alone can predict the difficult intubation in adult patients.

Head and neck surgery in a tertiary centre: Predictors of difficult airway and anaesthetic management

Introduction: The management of head and neck surgical patients is associated with increased morbidity and mortality, and so anticipating the difficult airway is important. Methods: We undertook a prospective survey on consecutive adult patients scheduled on the elective operating lists of four head and neck consultant surgeons. Data were collected over a 36 month period. Data included: patient characteristics; routine predictors of difficulty in airway management (bedside tests of the airway, a history of previous surgery or radiotherapy and the presence of airway symptoms); laryngoscopy grade; method of anaesthesia and airway management; and any airway complications arising during induction of anaesthesia and extubation. Results: The ‘study’ group consisted of 818 patients. The ‘direct laryngoscopy’ group contained 674 patients, that is, patients who had direct laryngoscopy and could therefore be classified as easy or difficult intubation. The prevalence of difficult intubation was 12.6%. Factors or tests that were statistically significantly associated with difficult intubation were: history of difficult airway; previous head or neck radiotherapy treatment; presence of airway symptoms; presence of moderate or severe limited neck movement; and short interdental distance. The sensitivity, specificity and positive predictive values were: history of difficult airway 16.5%, 98.6% and 63.6%; previous radiotherapy 12.9%, 96.6% and 35.5%; airway symptoms 42.9%, 69.6% and 15.9%; moderate/severe neck limitation 16.7%, 97.2% and 46.7%; Mallampati score 3 or 4, 38.8%, 83.8% and 25.8%; and interdental distance 9.4%, 98.8% and 53.3%, respectively. The Bonfils intubation fibrescope was the most commonly used indirect laryngoscopy device (63.9% of all such cases). Twenty-six patients (3.2%) had complications during their initial airway management after induction of anaesthesia. There was one case of ‘cannot intubate, cannot oxygenate’, which required an emergency tracheostomy. Conclusion: The prevalence of difficult intubation in head and neck surgical patients was higher than in the general population, but predictive tests for difficult intubation have poor to moderate value. In our study, rates of difficult face mask ventilation, failed intubation and complications during induction and extubation were low. However, serious morbidity, although rare, can still be encountered. Head and neck surgical patients can be managed safely in a tertiary centre where there is appropriate surgical and anaesthetic expertise in managing difficult airways.

Prevalence and prediction of difficult intubation in Nepalese population

Background: Prevalence of difficult intubation is estimated as 3 -18% during routine anesthesia. There are various bedside tests to predict the difficult intubation, like Mallampati test, Thyromental distance, Sternomental distance and mouth opening. However, the prevalence and prediction in Nepalese population is still not estimated. So this study is to see the prevalence and to compare the efficacy of airway parameters to predict the difficult intubation in Nepalese population.Methods: A prospective study was done to estimate the prevalence and prediction of difficult intubation in Nepalese population. During six months period, 182 patients who were undergoing routine surgery under General anesthesia were included in the study. Mallampati grading, thyromental distance, mouth opening and sternomental distance were recorded in preoperative assessment. Cormack and Lehane grading were done during intubation and Grade I and II are considered as easy intubation/ laryngoscopy and III and IV are considered as difficult intubation.Results: The prevalence of difficult intubation was 4.9%. Sensitivity of different tests were as follows; Mallampati test – 55%, thyromental distance – 33%, mouth opening – 22% and sternomental distance – 11%. The Specificity of the test as Mallampati test – 98%, thyromental distance – 89%, mouth opening – 96% and sternomental distance – 97%. So the Mallampati test is more sensitive and specific among the tests done.Conclusion: This prospective study shows that the prevalence of difficult intubation is not different in Nepalese population and the bedside predictors also are good tests that could be continued in our population.Journal of Society of Anesthesiologists of Nepal 2015; 2(1): 17-20

Early Identification of Patients at Risk for Difficult Intubation in the Intensive Care Unit

Difficult intubation in the intensive care unit (ICU) is a challenging issue.To develop and validate a simplified score for identifying patients with difficult intubation in the ICU and to report related complications.Data collected in a prospective multicenter study from 1,000 consecutive intubations from 42 ICUs were used to develop a simplified score of difficult intubation, which was then validated externally in 400 consecutive intubation procedures from 18 other ICUs and internally by bootstrap on 1,000 iterations.In multivariate analysis, the main predictors of difficult intubation (incidence = 11.3%) were related to patient (Mallampati score III or IV, obstructive sleep apnea syndrome, reduced mobility of cervical spine, limited mouth opening); pathology (severe hypoxia, coma); and operator (nonanesthesiologist). From the β parameter, a seven-item simplified score (MACOCHA score) was built, with an area under the curve (AUC) of 0.89 (95% confidence interval [CI], 0.85-0.94). In the validation cohort (prevalence of difficult intubation = 8%), the AUC was 0.86 (95% CI, 0.76-0.96), with a sensitivity of 73%, a specificity of 89%, a negative predictive value of 98%, and a positive predictive value of 36%. After internal validation by bootstrap, the AUC was 0.89 (95% CI, 0.86-0.93). Severe life-threatening events (severe hypoxia, collapse, cardiac arrest, or death) occurred in 38% of the 1,000 cases. Patients with difficult intubation (n = 113) had significantly higher severe life-threatening complications than those who had a nondifficult intubation (51% vs. 36%; P < 0.0001).Difficult intubation in the ICU is strongly associated with severe life-threatening complications. A simple score including seven clinical items discriminates difficult and nondifficult intubation in the ICU. Clinical trial registered with www.clinicaltrials.gov (NCT 01532063).

Prevalence of difficult intubation in a bariatric population, using the beach chair position

Prevalence of difficult intubation in a bariatric population, using the beach chair position

The Diagnostic Value of the Upper Lip Bite Test Combined with Sternomental Distance, Thyromental Distance, and Interincisor Distance for Prediction of Easy Laryngoscopy and Intubation: A Prospective Study

Accuracy of upper lip bite test (ULBT) has been compared with the Mallampati classification. In this study, we investigated whether the combination of the ULBT classification with sternomental distance (SMD), thyromental distance (TMD), and interincisor distance (IID) or a composite score can improve the ability to predict easy laryngoscopy and intubation compared with each test alone. In a prospective study, 380 patients who were scheduled for elective surgery were selected randomly and enrolled in the study. Before inducing anesthesia, the airways were assessed, and ULBT class, SMD, TMD, and IID determined. Laryngoscopic view according to the Cormack and Lehane grading system was determined after induction of anesthesia and Grades 3 and 4 defined as "difficult intubation." By using receiver operating characteristic analysis, the best cutoff points of the tests were calculated. Finally, sensitivity, specificity, positive and negative predictive values and accuracy of these tests and their combinations with the ULBT were calculated. The prevalence of difficult intubation was 5% (n = 19). Class III ULBT, IID <4.5 cm, TMD <6.5 cm, and SMD <13 cm were defined as predictors of difficult intubation. There was no significant difference regarding difficult intubation based on gender (P < 0.05), whereas there were significant differences between the older tests and laryngeal view (P < 0.05, Mc-Nemar test). Specificity and accuracy of the ULBT were significantly higher than TMD, SMD, and IID individually (specificity was 91.69%, 82.27%, 70.64%, and 82.27%, respectively, and accuracy was 91.05%, 71.32%, 81.84%, and 76.58%, respectively). The combination of the ULBT with SMD provided the highest sensitivity. We conclude that the specificity and accuracy of the ULBT is significantly higher than the other tests and is more accurate in airway assessment. However, the ULBT in conjunction with the other tests could more reliably predict easy laryngoscopy or intubation.

Prevalence of difficult intubation in a bariatric population, using the beach chair position

We retrospectively reviewed the anaesthetic charts of patients who had undergone bariatric surgery in our regional centre since the start of the service. We identified Cormack and Lehane grade of laryngoscopy, any difficulties associated with tracheal intubation, and the impact of age, gender and body mass index on laryngoscopy grade. The patients were anaesthetised in the in the 'beach chair' position prior to laryngoscopy. One hundred and ninety-two patients' notes were available for review out of a total of 198. Mean age was 43.3 years (SD 10.3) and mean BMI 50.8 (SD 8.0). Grade of laryngoscopy was unrecorded in 20 patients. Of the 192 patients, 162 (84%) had a Cormack and Lehane grade of 1 or 2. Nine (4.7%) patients were graded as 3 and only one patient had a grade 4 laryngoscopy. There were two cases (1%) of difficulty in intubation. A bougie was used 16 times (8%). Logistic regression showed that age was a significant factor for increasing laryngoscopy grade (p = 0.0102) but that BMI was not (p = 0.6271).

Prédicteurs préopératoires ďune intubation difficile chez des patients qui présentent de ľapnée obstructive du sommeil

It has been speculated that the severity of obstructive sleep apnea syndrome (OSAS) is related to difficult intubation. However, this has not been confirmed in OSAS patients. Thus, we undertook a retrospective study to assess this relationship in patients who had undergone uvulopalatopharyngoplasty (UPPP) surgery for OSAS.A retrospective case-control study was undertaken following approval from the Institutional Review Board on human studies. The data from 90 patients with a polysomnograph-confirmed diagnosis of OSAS, who had undergone UPPP surgery under general anesthesia, were used to evaluate the apnea-hypopnea index (AHI), the preoperative lowest arterial saturation, the occurrence of difficult intubation as assessed by the operator intubation difficulty scale score, extubation time, lowest arterial saturation in postanesthesia care unit, and length of stay in postanesthesia care unit. We compared OSAS patients with 90 age and sex-matched control patients with respect to the prevalence of difficult intubation.The prevalence of difficult intubation was higher in the OSAS group than in the control group (16.7% vs 3.3%, P = 0.003). When evaluating the OSAS group according to the occurrence of difficult intubation, AHI was significantly higher in the difficult intubation subgroup (67.4 +/- 22.5 vs 49.9 +/- 28.0, P = 0.026), and patients with an AHI >or= 40 showed a significantly higher prevalence of difficult intubation.This study shows that the occurrence of difficult intubation can be predicted using AHI in patients who undergo UPPP surgery for OSAS.

Prevalence and prediction of difficult intubation in Chinese women.

We conducted a prospective, blind observational study to investigate the prevalence and prediction of difficult intubation in Chinese women. Two groups of Chinese women were studied (151 pregnant and 260 non-pregnant). The prevalence of difficult intubation was 1.99% in the pregnant and 1.54% in the non-pregnant group. The difference was not statistically significant. Predictive variables for difficult intubation, including modified Mallampati class, thyromental distance and atlanto-occipital extension, had high sensitivity but low positive predictive value when used alone. A shorter thyromental distance had to be used as the criterion for prediction in Chinese women. Combination of predictive variables could improve the positive predictive value.